1 files changed, 34 insertions, 6 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 89b9535cda19..525790a38f6d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3295,6 +3295,28 @@ void btrfs_add_delayed_iput(struct inode *inode)
 		wake_up_process(fs_info->cleaner_kthread);
 }
 
+static void run_delayed_iput_locked(struct btrfs_fs_info *fs_info,
+				    struct btrfs_inode *inode)
+{
+	list_del_init(&inode->delayed_iput);
+	spin_unlock(&fs_info->delayed_iput_lock);
+	iput(&inode->vfs_inode);
+	if (atomic_dec_and_test(&fs_info->nr_delayed_iputs))
+		wake_up(&fs_info->delayed_iputs_wait);
+	spin_lock(&fs_info->delayed_iput_lock);
+}
+
+static void btrfs_run_delayed_iput(struct btrfs_fs_info *fs_info,
+				   struct btrfs_inode *inode)
+{
+	if (!list_empty(&inode->delayed_iput)) {
+		spin_lock(&fs_info->delayed_iput_lock);
+		if (!list_empty(&inode->delayed_iput))
+			run_delayed_iput_locked(fs_info, inode);
+		spin_unlock(&fs_info->delayed_iput_lock);
+	}
+}
+
 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
 {
 
@@ -3304,12 +3326,7 @@ void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
 
 		inode = list_first_entry(&fs_info->delayed_iputs,
 				struct btrfs_inode, delayed_iput);
-		list_del_init(&inode->delayed_iput);
-		spin_unlock(&fs_info->delayed_iput_lock);
-		iput(&inode->vfs_inode);
-		if (atomic_dec_and_test(&fs_info->nr_delayed_iputs))
-			wake_up(&fs_info->delayed_iputs_wait);
-		spin_lock(&fs_info->delayed_iput_lock);
+		run_delayed_iput_locked(fs_info, inode);
 	}
 	spin_unlock(&fs_info->delayed_iput_lock);
 }
@@ -4014,6 +4031,17 @@ skip_backref:
 		ret = 0;
 	else if (ret)
 		btrfs_abort_transaction(trans, ret);
+
+	/*
+	 * If we have a pending delayed iput we could end up with the final iput
+	 * being run in btrfs-cleaner context.  If we have enough of these built
+	 * up we can end up burning a lot of time in btrfs-cleaner without any
+	 * way to throttle the unlinks.  Since we're currently holding a ref on
+	 * the inode we can run the delayed iput here without any issues as the
+	 * final iput won't be done until after we drop the ref we're currently
+	 * holding.
+	 */
+	btrfs_run_delayed_iput(fs_info, inode);
 err:
 	btrfs_free_path(path);
 	if (ret)